1. Field of the Invention
The present invention relates to an improved system for providing pathway indication through unlit areas. For example, outdoor parking lots are often illuminated by light poles which, for economic reasons, are often designed to be automatically turned off after a set time, for example midnight. After this shut-off time, navigating or exiting the parking lot can be extremely hazardous. In fact, the light poles themselves can be a significant obstacle to safe egress of the parking lot.
2. Summary of Related Art
U.S. Pat. No. 4,801,928 discloses an egress direction indication system utilizing an indicator with at least three electroluminescent lamps in a linear arrangement and circuitry for sequentially illuminating the lamps on a repeating basis, in order, from one end of the linear arrangement to the other. The lamps are mounted on a circuit board with a lens covering the lamps. The circuitry lights in a first direction under one sensed condition and lights in a second direction in a different sensed condition.
U.S. Pat. No. 5,815,068 discloses a light system with controllable light sources positioned along alternative routes of movement to serve as an optical means for influencing people to follow an indicated route to a selected area. A command system allows a selection to be made controlling the direction of movement to be indicated. Light emitting diodes (LEDs) are a preferred light source.
U.S. Pat. No. 5,343,375 discloses an emergency egress illuminator and marking light strip. This patent teaches a system for the lighting of a floor of an emergency egress passageway during clear air conditions and also marks an emergency escape path. The system utilizes two narrow strings of narrow cone LEDs each in a transparent tubular housing, which is mounted on the passageway wall.
While these systems are suitable for their intended purposes, they are not ideally designed for applications such as described above. This is because the present invention provides improved energy efficiency over the systems known in the art, and is thus more economical. Additionally, the present invention is optimized to operate in conditions of power failure or other interruptions of main power supply.
Therefore, it is an object of the present invention to provide an economical lighting system to allow safe egress from a darkened area, such as a parking lot, when a primary light system is unavailable.
In accordance with the present invention, there is provided a photocell for converting sunlight into electrical energy and a storage cell for storing that energy for a future time. The photocell and the storage cell may be combined into the same unit, but this is not necessary. The storage device is connected, by way of a switching apparatus, to an LED or series of LEDs which provide sufficient light to illuminate the darkened area sufficiently to allow safe egress from the darkened area.